But a furious Abbott told PoliticsHome: “The people of this country have suffered a series of terrorist tactics. The Government's own security threat rating implies there could be further attacks.

“Therefore the public has a right to know if any governments or foreign or domestic agencies or individuals are funding terrorism in this country, and what the UK government intends to do to prevent that.

“Of course, security intelligence should not be compromised but this is easily achieved by redaction and other matters. The Government would never have commissioned this report if it considered this problem was insurmountable.

“Instead, there is a strong suspicion this report is being suppressed to protect this Government's trade and diplomatic priorities, including in relation to Saudi Arabia. The only way to allay those suspicions is to publish the report in full.”

Theresa May had been accused of hiding the outcome of the review which was launched by David Cameron back in 2015 as part of an agreement with the Liberal Democrats.

Lib Dem leader Tim Farron said today: “The Government hoped to sneak out what it thinks are the top lines of a report, no-one has seen on a busy day hoping no-one would notice. This decision is utterly shameful…

“We cannot tackle the root causes of terrorism in the UK without full disclosure of the states and institutions that fund extremism in our country.”

And Green co-leader Caroline Lucas said: "The Government's refusal to publish this report, and this utterly vague statement, are completely unacceptable.

“The statement gives absolutely no clue as to which countries foreign funding for extremism originates from - leaving the Government open to further allegations of refusing to expose the role of Saudi Arabian money in terrorism in the UK.”

In a Written Statement today Rudd said the review offers “the best picture we have ever had of how extremists operating in the UK sustain their activities”.

But she added: “Having taken advice, I have decided against publishing the classified report produced during the review in full.

“This is because of the volume of personal information it contains and for national security reasons.”

Privy councillors from the opposition parties – including Labour leader Jeremy Corbyn – will have access to the full document but will be sworn to keep its contents secret.

Rudd revealed there were a “small number of organisations” practising extremism for which “overseas funding is a significant source of income”.

It was widely thought Saudi Arabia is a major source of that overseas funding but the UK is reluctant to damage diplomatic ties with the Kingdom to which it sells billions of pounds worth of arms.

She also said some individuals who have been funded from abroad to study “highly socially conservative” forms of Islam have since become “of extremist concern”.

Rudd said extremist organisations in the UK sometimes “receive hundreds of thousands of pounds a year” from donors who may not know or support their full agenda.

She said some will hide as charities and improving awareness and regulation was the way forward – including a new requirement on charities to declare overseas funding sources.